Nintendo: SNES - ironically the only Nintendo system I have never owned. However, I did get to play it plenty. This system had some of the greatest games of all time on it, CHRONO trigger, ffvi, super Mario rpg, and many more. Only complaint is the controller sucked.
Sony: PS1 - the original PlayStation still has one of the best game libraries to date, as well as the best RPG of all time, Suikoden 2. It was an RPG powerhouse that destroys all other systems in that genre.
Microsoft: Xbox 360 - the 360 is my favorite system ever made. Microsoft did a freaking amazing job of expanding the possibilities in gaming and pushing new boundaries in games. Before the 360 I would pretty much just play RPG’s, but amazing games like halo and gears pushed my interests into new genre’s especially with the development of a proper online to go with them. It was also home to some of the best RPG’s of the generation with mass effect, lost odyssey, and tales of vesperia. Microsoft hit it out of the park that gen, at least for the first half.
Sega: genesis - this was my childhood. My favorite game of all time is shining force 2. I wish sega would pull their head out and make a proper new shining force game...